1. Field of the Invention
The present invention relates to a washing machine, and more particularly, to a method of controlling a water supplying step and a draining step in a washing machine having no anti-siphoning device.
2. Discussion of the Related Art
In general, a washing machine is an apparatus for removing dirt from laundry through such steps as washing, rinsing, and dewatering in accordance with a program stored in a microcomputer under the control of a user. Basically, a tub is filled with water for carrying out a washing step or a rinsing step, which is drained using a drain pump after each step to permit refilling for further washing or rinsing steps. The drain pump, installed in a is drainpipe for draining the tub to the exterior of the washing machine, is turned off when draining is finished.
In a washing machine as above, there is an inherent siphonic phenomenon that may occur with draining, whereby an unintended continuation of a draining step persists even if the drain pump is turned off. Thus, if an attempt to refill the tub is initiated immediately following the draining, by way of the stored program or otherwise, the siphonic phenomenon may continue to drain the tub while filling progresses. That is, if water remains in the drainpipe of the washing machine as the draining step comes to an end, a siphonic phenomenon will tend to continue to act on the remaining water, to counter a refilling of the tub in the event that a subsequent user-selected step, such as washing or rinsing, is performed.
To prevent the occurrence of such a phenomenon, a washing machine may be provided with an anti-siphoning device. Such devices, however, are expensive and are thus cost-prohibitive for the manufacture of an ordinary consumer product such as a home appliance. In a washing machine without such an anti-siphoning device, water is wasted and the refilling process may be slowed accordingly. Moreover, if a substantial amount of water remains when a subsequent user-selected step is to be executed, for example, due to the counterproductive refilling of water simultaneous with its draining, a simple draining of the water may also unnecessarily waste water.